The present invention relates to a modified cordless electric power drill, and more specifically to methods and systems for providing power assisted starting for a variety of gasoline engine devices.
Many gasoline engines use a pull-cord in which a cord is wound about a pulley which is coupled to the engine's crankshaft. Using the pull-cord to start an engine requires a certain level of physical strength and range of motion. Because of this, many people have difficulty using a pull-cord to start an engine. Accordingly, various mechanical starters have been developed to help start gasoline engines.
Such prior art devices have included expensive and complex power starting units such as those utilizing a starter ring and Bendix drive with an electric starter and battery. Although these units work satisfactorily, battery charging and replacements are cumbersome while permanently mounted in the device, they increase weight and the initial cost of the lawn mower. In an attempt to devise a more economically feasible starter, prior proposals have suggested using a coupler to connect an electric drill to the crankshaft to provide the torque needed to turn the crankshaft. Certain of these devices have proved to be hazardous to operate due to the difficulty in disengaging the coupler from the engine once the engine is started. Certain embodiments also required a special mounting structure on the lawn mower which required modifying the existing crankshaft configuration.
In previous patents, an uncovered hex shank socket extension with a linkage device has been used to engage an existing hex nut of the bolt securing a flywheel to its crankshaft. This open configuration may cause safety concerns upon removal of the starter as kick-back from the starter device caused injuries. For example, U.S. Pat. No. 3,596,647 disclosed a large rig to hold a drill in place. This rig is only applicable, however, for larger equipment and lacks a shielding device for the rotating linkage mechanism. Other systems employ a simple clutch to assist in the disengagement of the linkage of the starter mechanism. However, these clutches also failed to remedy the danger associated with kick-back. For example, U.S. Pat. No. 4,365,596 discloses a sleeved drive shaft that rotates upon withdrawal from the linkage. Moreover, the device disclosed in the '596 patent does not provide any mechanism for locking the starter in place to prevent kick-back.
For the foregoing reasons, there is a strong need for a system for providing power assisted starting for a variety of gasoline engine devices that provides adequate shielding for the user to alleviate safety concerns. The present invention provides these and other advantageous results.